Apparatus tor directive transmission



F. S. McCULLOUGH.

APPARATUS FOR DIRECTIVE TRANSMISSION OF ELECTROMAGNETIC WAVES.

APPLICATION HLED OCT-30,1916.

Z OH O a 3. 3 4 I Y1 25W w H. .WM 7 N am 0 flu M m 5 M w M F w r M I ZF. S. McCULLOUGH.

APPARATUS FOR DIRECHVE TRANSMISSION OF ELECTROMAGNETIC WAVES.

APPLICATlON FILED OCT-30. 1916.

Patented Jan. 17, 1922.

2 SHEETSSHEET Z- [TED STATES PATENT OFFICE.

FREDERICK S. MGCULLOUGH, OF CLEVELAND, 01-110, ASSIGNOR T 0F CLEVELAND,OHIO.

GLENN L. an-rm,

APPARATUS FOR DIRECTIVE TRANSMISSION OF ELECTROMAGNETIC WAVES.

Application filed October 30, 1916.

To all whom it may concern:

Be it known that I, FREDERICK S. Mo- (lunnoueir, a citizen of the UnitedStates, residing at Cleveland, in the county of Cuyahoga and State ofOhio, have invented a certain new and useful Improvement in Apparatusfor Directive Transmission of Electromagnetic lVaves, of which thefollowing is a full, clear, and exact description, reit'erence being hadto the accompanying drawings.

This invention relates to an improved system of transmission ofelectromagnetic waves for purposes of wireless co1nmunication, signalingetc. The general object is to increase the efficiency of and to simplifysuch apparatus.

A more specific object of this invention is to so construct theapparatus that it may be effectively used. for actuating selectively oneor more of a pll'irality of receiving devices by directive transmissionof electro magnet waves from one or more transmitting apparatus. Theinvention is particularly useful for signaling successively individual.members of a series of receiving devices the transmitting device beingso arranged as to travel in a pathway leading past said receivingdevices.

Another specific object of the invention is to arrange the apparatusthat it may be well adapted for use in a system including a plurality ofreceiving members located at intervals along a traclrway or guideway andin close proximity thereto, while a coacting transmitting device maycommunicate selectively with the receiving devices as it IS moved alongthe trackway or guideway past the same.

forth in the following description which refers to the drawingsillustrating a preferred embodiment thereof. The essentialcharacteristics of the present invention are set forth in the claims.

1' have shown, in the drawings illustrations of my invention indiagrammatic form,-

in order that it may be more readily understood. as it is apparent thatthose skilled in the art may readily embody the invention with propermechanical devices corresponding to the diagrammatic illustrations.

In the drawings. Fig. 1 is a diagrammatic view illustrating a simpleform of trans-l Specification of Letters I'atent.

Patented Jan. 17, 1922.

Serial No. 128,375.

mission and receiving apparatus; Fig. 2 is a similar view showing amodified form of receiving apparatus; Figs. 3 and d are a side elevationand a front elevation respectively, of a particular form ofparabolicshaped capacity members; big. 5 is a View showing a series ofreceiving station and a transmission device coacting therewith andadapted to travel in parallel relation thereto. In this figure thetransmitting device is illustrated in solid lines in the inter mediateposition, and in dot and dash lines in the other positions coacting withother receiving stations. Fig. 6 illustrates a slightly modified form oftransmitting and receiving stations adapted to be used in a similarmanner. F ig. 7 is a cross-section on an enlarged scale of the tube 40showing the wire in heating contact with the glass.

Referring to Fig. 1, 10 indicates a suitable high frequency generatorwhich is illustrative of any means for generating electromagnetic wavesof high frequency.

One pole of this generator is shown as connected to. the ground 12 by awire 13. From the other pole a wire 14: leads to a coil 16 providing avariable inductance, the con tact 17 being movable along the same. Thisinductance is shown as connected with a capacity member indicated at 20,which is preferably of the form shown in Figs. 3 and 4t, and which willbe later more specifically described.

By arranging the capacity member 20 or the induction portion 16, orboth, so that they may be adjusted, they may be brought into properproportion to the desired wave length. The frequency of the generatormaybe varied by changing its speed.

At is indicated a receiving capacity similar to the transmittingcapacity 20 and connected by a wire with a suitable receiver indicatedat 353. and connected to the ground 12 by a wire 33. The telephone at 32is merely symbolic-a1 of any suitable receiving apparatus. and itsdiaphragm is not intended to vibrate at radio frequencies.

Referring to Fig. 2 and Fig. 7, in which is illustrated an apparatusmore particularly adapted for relay signaling by directive transmissionof electromagnetic Waves, the transmitting device is substantially thesame as shown in Fig. 1, while the receiving de vice is shown ascomprising the receiving capacit 25 and. hot cathode tube to lmv- "43-and thence to the wire ll.

. may contain a residuum 0; an inert gas such the variable resistance58, :tor A rztino' tl current n the c1rcuit.

inc; connections and etZleading iron the l l e capacity to the ca lodetuhc the ground respec .yely. ll itliin th s tube are a plurality ofnnnute Wires i r'ou' iteil 5Tb surround 1Q lllil'll 1 12:.

as nitrogen. The coil cl w this tube and is connected quency alternatingcurrent nerator in circuit with the generator and t The yr y o thegenerator 56 may be variel by changing itsspeed. A branch circuit, 57.runs to the Wire 4-2.

The rap1dly alternating electrification or changing of the currents inthe coil causes the latter to become heated. This heated co1lSUIlOHIlCllIlQ; and substantially in contact with the glass tube orqhilre causes the latter to become heated the flowing through Wires 4A-result of radiation and conduct-ion of suvh hea. The filament or Wires 1are heated byv the charge effect placed upon the capacity member 25,which creates current in connection with the ground 12, making acomplete circuit through the transmitter to d receive" I;

this manner, therefore. it Will he und :tood that a maximum emission ofelectrons is obtained.

The frequency of generator should be the same as that of generator 10 atthe transinitting station and a rapidly oscillating; field iscreeted inthe tube, Within the coil Under these circumstances. When the waves fromthe transmitting station are received at the receiving); station on thereceiving capacity'25; and the oscillations are transmitted by the Wire41 to. the wire or wires +1 1- 111 the tube, the flow oi electrons -letween the Wire or Wires 4-;- and the plate a5 is increased to an extentsullioiont to perrnit a flow of current in the circuit including thebattery 47 and relay/tS reat enough to operate the relay 48. so thatcurrent will lion; in the circuit containing the indicating d' fvice 52,andcause the latter to give a si 'nal.

The parabolic. capacity device, illustrated particularly in- Figs. 3 and4, is shown as made up of a continuous fiat metal surface =Warped'into'the shape er; a parabolic re z-tlector.

prlses a thin ribbon of metal connected This flat surface preferablycornat each end to conductors 60 and bent 1e peatedly upon itsel'l in atortuous path, forming a series of loops (32 each connected at one endwith the loop ncercr tl o Wire (30 sureface ot the reflector. Thisdisposi H111 of the conductor also reduces the indumeneo to a minimum.

is capacity such as just described has hccn found by experiment to hevery sensitive and l with a receiving appaell ective when used ratus.

ln cairyin; out the Sli tt'llii' ohjcct ol' acting a plurality ofreceiving devices by directive transmission oi electroauinructu' vavesfrom a station having its capacity traveling in a pathway in iixn'allclrelation to the capacities ot the l'G-(llVlllfl derives and Withoutinterference. l have iii-reused the system shovvu in Fig. 7 in which thegene]'ator il lll lll'ltfliill to l6 and ground ii) are illustratedsuhstantially as in l' isr. l and in which the apacity '70 may he of.any desired shape or term.

The capacities are adapted to receive impulses 'li nn the directivecapacity Tl) only when the capacity "I is in pr n-tinill'y or positionsuhstantially opposite one ol' the capacities 75.

It this the directive lJHNS HlS UEI device is a lo he moved O lQf apath- ("OlllPS pos t on which into the line it shown in soliv'l cs a eswith the rcvciviiu; elation directly o positc. 'lhc positions ll andiudicute the sending device in position to trr, impulses to the,-.orrcspondinn rece' .ations.

adapted to receive impulses l'roni :1 caparity nieinher R5 \vlicu thecapacity.inculhers are hrougrht into the relative po itions illustratedin this llgruro. 'lhis particular :nwziipgonuait is n clul i instanceswhere. grounding}; the c rcuit would loud in misdirect the same as theca rarity ElKlll u! nu: v he made more truly selective it oporalive onlywhen hoth capacities are hrougrht into close proximity. as illustrated.

The arrangement of the system just doscrihed particularly usotul.xloreruunple. in signaling; systems tor elevators and the like.

The capacity members 70, 75. fil and are diagrammatically illustrated asflat plates, but, in instances where the distance between the capacitymembers is compan atively great capacity members such as illustrated inFigs. 3 and l may be used with advantage, as the waves might then bedirected toward a particular station which would receive suilicientenerg by reason of the directing action of such a capacity memher, toactuate its receiving device while those toward which the capacitymember is not directed would receive no impulses sufiicient to register.

From the foregoing description it will be seen that I have provided asystem and apparatus for wireless transmission, capable of selectivelycommunicating from one or more stations to any of a series o'lt'stations and that when the distance between the Ell/Eltions isappreciable, the directive capacity member herein described willfunction very usefully in controlling); the selection of the receivingstation.

Having thus described my inventioin What I claim is:

1. In a system of wireless tra1smission,

the combination oi? means tor generating electro-magnetic waves, adirective capacity member associated with said means and comprising aconductive flat ribbon bent upon itsell in asuccession of loops andarranged in the form of a parabolic reflecton 2. In a wireless signalingapparatus, a means for receiving or projecting electromagnetic waves,comprising a capacity member, made up of a flat conducting element whichis oblong in cross section and arranged edge to edge in courses spacedapart.

3. A. capacity member for use in a wire less transmission system,consisting cit a conductor convoluted into the form of a slreletonparaboloid.

i. A capacity member for use in a Wireless transmission systemconsisting of a corn ductor convoluted into the form of a skeletonparaboloid, the conductor being; elongated in cross section in thedirection of the parabolic surface. I

5. Ax. capacity member for use in a wire less transmission systemcomprising a slreleton paraboloid consisting of a substantially fiatmetallic ribbon convoluted into parallel strips with the edges. adjacentbut separated.

6. in a wireless systeim an element con sisting; f a continuous thin,llat conductor, oblong in cross-section disposed edge to edge in aseries of adjacent coiu'ses said conductor being; bent baclr upon in aparabolic surface 7. lfn a wireless system an element consisting oil? acontinuous thin fiat conductor, oblong in cross-section, disposed edgeto elge in series of adjacent courses, the adjacent courses running inopposite dircc' tions, in a parabolic surface.

8. In a wireless system, an element consisting oil a continuous thin.tlat conductor, oblong; in cross-section, so disposed in a parabolicsurface, as to increase its capacitance and reduce its inductance llntestimony whereof, l hereunto aiiii; my sign ature.

FREDERICK El. lillcGUlal'iOlJGrHn

